:root {
    --primary-color: #4361ee;
    --secondary-color: #3f37c9;
    --accent-color: #4895ef;
    --light-color: #f8f9fa;
    --dark-color: #212529;
    --text-color: #495057;
    --muted-color: #6c757d;
}

body {
    background-color: #f5f7ff;
    color: var(--text-color);
    font-family: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 25px 0;
    border-radius: 0 0 20px 20px;
    box-shadow: 0 4px 20px rgba(67, 97, 238, 0.15);
    text-align: center;
}

.header-title {
    font-weight: 600;
    font-size: 1.8rem;
    margin-bottom: 5px;
}

.header-subtitle {
    font-size: 1rem;
    opacity: 0.9;
}

.register-container {
    max-width: 500px;
    margin: 40px auto;
    padding: 0 15px;
    flex: 1;
}

.register-card {
    background-color: white;
    border-radius: 15px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.08);
    padding: 30px;
    position: relative;
    overflow: hidden;
}

.register-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
}

.register-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 25px;
    text-align: center;
}

.form-group {
    margin-bottom: 20px;
    position: relative;
}

.form-label {
    font-weight: 500;
    margin-bottom: 8px;
    display: block;
    color: var(--dark-color);
}

.form-control {
    height: 48px;
    border-radius: 8px;
    border: 1px solid #e0e0e0;
    padding-left: 15px;
    transition: all 0.3s ease;
}

.form-control:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.25rem rgba(67, 97, 238, 0.15);
}

.input-icon {
    position: absolute;
    right: 15px;
    top: 49px;
    color: var(--muted-color);
    font-size: 16px;
    cursor: pointer;
}

.gender-group {
    display: flex;
    gap: 15px;
    margin-top: 10px;
}

.gender-option {
    flex: 1;
    position: relative;
}

.gender-option input {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.gender-label {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 48px;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.gender-option input:checked + .gender-label {
    border-color: var(--primary-color);
    background-color: rgba(67, 97, 238, 0.1);
    color: var(--primary-color);
}

.gender-label i {
    margin-right: 8px;
}

.btn-register {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border: none;
    height: 48px;
    border-radius: 8px;
    font-weight: 500;
    font-size: 1rem;
    width: 100%;
    margin-top: 20px;
    transition: all 0.3s ease;
}

.btn-register:hover {
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(67, 97, 238, 0.3);
}

.login-link {
    text-align: center;
    margin-top: 20px;
    font-size: 15px;
}

.login-link a {
    color: var(--primary-color);
    font-weight: 500;
    text-decoration: none;
}

.login-link a:hover {
    text-decoration: underline;
}

.form-text {
    font-size: 13px;
    color: var(--muted-color);
    margin-top: 5px;
}

.password-strength {
    height: 4px;
    background-color: #e9ecef;
    border-radius: 2px;
    margin-top: 10px;
    overflow: hidden;
}

.strength-bar {
    height: 100%;
    width: 0;
    background-color: #dc3545;
    transition: width 0.3s, background-color 0.3s;
}

.footer {
    text-align: center;
    padding: 20px 0;
    color: var(--muted-color);
    font-size: 13px;
    margin-top: auto;
}

@media (max-width: 576px) {
    .register-card {
        padding: 25px 20px;
    }

    .register-title {
        font-size: 1.3rem;
    }

    .form-control {
        height: 44px;
        padding-left: 12px;
    }

    .btn-register {
        height: 44px;
    }

    .gender-group {
        /*flex-direction: column;*/
        gap: 10px;
    }
}